Osteoarthritis (OA) is the most common joint disease and is a leading cause of disability worldwide [1,2]. The physical impairment from OA of a single lower extremity joint is equivalent to that reported for major life-altering disorders such as end-stage kidney disease and heart failure [3]. The causes of OA are not well understood. However, joint trauma is a leading etiological factor [1,2,4]. Intra-articular fracture, joint dislocations, and other joint injuries can lead to post-traumatic osteoarthritis. Although they are a subset of joint trauma, ACL and meniscal injuries are the most common injuries treated by orthopaedic surgeons [11, 12]. Despite recent advances in operative and non-operative treatment of ACL injuries, patients sustaining ACL and related injuries suffer a 50% chance of compromised knee function ten years after injury and have a ten-fold increased risk of OA compared to those who did not have a joint injury [13-15]. Formed in 1972 primarily as a forum for dissemination of developments in clinical technique and new research findings, the American Orthopaedic Society for Sports Medicine (AOSSM) is now a world leader in sports medicine education, research, communication, and fellowship. The Society and its members focus on the treatment of injuries commonly sustained by active individuals and the restoration of active lifestyles. The AOSSM recognizes the physical, emotional, and socioeconomic burdens joint injury and post-traumatic OA places on athletes, active individuals, and society in general. The AOSSM Post-joint Injury Osteoarthritis Conference II will be held December 2-5, 2010 in New Orleans, LA at the Ritz-Carlton New Orleans. The meeting is timely, and a logical follow-on to the momentum generated from the AOSSM/NIH R-13 Post-joint Injury Osteoarthritis Conference held December 11-14, 2008. The proposed conference brings together leaders in clinical research and experts in new quantitative clinical assessment modalities together to discuss and design a multi-center clinical study of human subjects following ACL injury for the possible development of a clinical initiative addressing post-joint injury OA. SIGNIFICANCE: The ultimate goal of establishing prospective clinical study cohorts of individuals at risk for post-traumatic OA is to facilitate the development of new collaborative approaches for early disease modifying treatments. Successful approaches would be potentially more broadly applicable not only to joint injury in general and also to the early diagnosis and treatment of cartilage injury and degeneration as strategies to reduce the total disease burden of osteoarthritis.